<?php

namespace Tools;

class Page {
    private $total; //数据表中总记录数
    private $listRows; //每页显示行数
    private $limit;
    private $uri;
    private $pageNum; //页数
    private $config=array('header'=>"个记录", "prev"=>"上一页", "next"=>"下一页", "first"=>"首 页", "last"=>"尾 页");
    private $listNum=8;
    /*
     * $total
     * $listRows
     */
    public function __construct($total, $listRows=10, $pa=""){
        $this->total=$total;
        $this->listRows=$listRows;
        $this->uri=$this->getUri($pa);
        $this->page=!empty($_GET["page"]) ? $_GET["page"] : 1;
        $this->pageNum=ceil($this->total/$this->listRows);
        $this->limit=$this->setLimit();
    }

    private function setLimit(){
        return "Limit ".($this->page-1)*$this->listRows.", {$this->listRows}";
    }

    private function getUri($pa){
        $url=$_SERVER["REQUEST_URI"].(strpos($_SERVER["REQUEST_URI"], '?')?'':"?").$pa;
        $parse=parse_url($url);



        if(isset($parse["query"])){
            parse_str($parse['query'],$params);
            unset($params["page"]);
            $url=$parse['path'].'?'.http_build_query($params);

        }

        return $url;
    }

    function __get($args){
        if($args=="limit")
            return $this->limit;
        else
            return null;
    }

    private function start(){
        if($this->total==0)
            return 0;
        else
            return ($this->page-1)*$this->listRows+1;
    }

    private function end(){
        return min($this->page*$this->listRows,$this->total);
    }

    private function first(){
        $html = "";
        if($this->page==1)
            $html.='';
        else
            $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=1'>{$this->config["first"]}</a>&nbsp;&nbsp;";

        return $html;
    }

    private function prev(){
        $html = "";
        if($this->page==1)
            $html.='';
        else
            $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=".($this->page-1)."'>{$this->config["prev"]}</a>&nbsp;&nbsp;";

        return $html;
    }

    private function pageList(){
        $linkPage="";

        $inum=floor($this->listNum/2);

        for($i=$inum; $i>=1; $i--){
            $page=$this->page-$i;

            if($page<1)
                continue;

            $linkPage.="&nbsp;<a href='{$this->uri}&page={$page}'>{$page}</a>&nbsp;";

        }

        $linkPage.="&nbsp;{$this->page}&nbsp;";


        for($i=1; $i<=$inum; $i++){
            $page=$this->page+$i;
            if($page<=$this->pageNum)
                $linkPage.="&nbsp;<a href='{$this->uri}&page={$page}'>{$page}</a>&nbsp;";
            else
                break;
        }

        return $linkPage;
    }

    private function next(){
        $html = "";
        if($this->page==$this->pageNum)
            $html.='';
        else
            $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=".($this->page+1)."'>{$this->config["next"]}</a>&nbsp;&nbsp;";

        return $html;
    }

    private function last(){
        $html = "";
        if($this->page==$this->pageNum)
            $html.='';
        else
            $html.="&nbsp;&nbsp;<a href='{$this->uri}&page=".($this->pageNum)."'>{$this->config["last"]}</a>&nbsp;&nbsp;";

        return $html;
    }

    private function goPage(){
        return '&nbsp;&nbsp;<input type="text" onkeydown="javascript:if(event.keyCode==13){var page=(this.value>'.$this->pageNum.')?'.$this->pageNum.':this.value;location=\''.$this->uri.'&page=\'+page+\'\'}" value="'.$this->page.'" style="width:25px"><input type="button" value="GO" onclick="javascript:var page=(this.previousSibling.value>'.$this->pageNum.')?'.$this->pageNum.':this.previousSibling.value;location=\''.$this->uri.'&page=\'+page+\'\'">&nbsp;&nbsp;';
    }
    function fpage($display=array(0,1,2,3,4,5,6,7,8)){
        $html[0]="&nbsp;&nbsp;共有<b>{$this->total}</b>{$this->config["header"]}&nbsp;&nbsp;";
        $html[1]="&nbsp;&nbsp;每页显示<b>".($this->end()-$this->start()+1)."</b>条，本页<b>{$this->start()}-{$this->end()}</b>条&nbsp;&nbsp;";
        $html[2]="&nbsp;&nbsp;<b>{$this->page}/{$this->pageNum}</b>页&nbsp;&nbsp;";

        $html[3]=$this->first();
        $html[4]=$this->prev();
        $html[5]=$this->pageList();
        $html[6]=$this->next();
        $html[7]=$this->last();
        $html[8]=$this->goPage();
        $fpage='';
        foreach($display as $index){
            $fpage.=$html[$index];
        }

        return $fpage;

    }


}
